"When this incident occurred in May, I indicated from the outset that I would plead guilty. That is what I have done today," she said.

"I haven't made any excuses. I have fronted the court like everybody else.

"I did the wrong thing. I made a mistake and I asked for the matter to be dealt with in the usual way, which it has been today.

"I thank the police for their work, the court for their work."

Ms Credlin says she will now continue to get on with her job.

"As you may well know, I have a job to do myself so I am headed back to work now," she said.

"I accept there is media attention. Justice doesn't have to be done, it has to be seen to be done.

"But now that the matter is resolved, you will understand I have no further comment to make."

Ms Credlin was expected to face court in July, but had her case delayed so it did not interrupt her commitments during the federal election campaign.

Magistrate Doogan ordered Ms Credlin pay $69 in court costs.

Outgoing Federal Attorney-General Mark Dreyfus says his Liberal counterpart has shown poor judgement by providing a character reference for a court case.

Mr Dreyfus says someone else should have provided the character reference, not Senator Brandis.

"I think it shows poor judgement on his part," he said.

"The Attorney-General, and we understand George Brandis has been designated as the person who is to become Attorney-General, is someone who stands in a special position in relation to the court system as the first law officer."